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48) Republic Day 2021: Parade timing security arrangements traffic prohibitions to Delhi Metro solutions - All you need to know

India Republic Day -- Republic Day 2021 Parade Routine Chief Guest Security Preparations: The parade normally views thousands of people and foreign dignitaries invited to see the parade. Nonetheless the number of guests and they has been restricted due to the coronavirus pandemic this time. Republic Time 2021 Parade Timings Main Guest Delhi Metro Companies: India will celebrate it is 72nd Republic Day about January 26. This day is actually marked to celebrate the day on which the Constitution associated with India came into being in 1950. On this day the Republic Day parade takes place to display the military might and also the rich cultural heritage with the country. The parade normally sees thousands of people and overseas dignitaries invited to see the attend. However the number of guests along with attendees has been restricted as a result of coronavirus pandemic this time. This season there will be no chief visitor or foreign dignitaries about Republic Day. The number of race f
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Alpha Centauri

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Alpha Centauri (Latinized from α Centauri , abbreviated Alpha Cen or α Cen ) is the closest star system and closest planetary system to Earth's Solar System at 4.37 light-years (1.34 parsecs) from the Sun. It is a triple star system, consisting of three stars: α Centauri A (officially Rigil Kentaurus ), α Centauri B (officially Toliman ), and α Centauri C (officially Proxima Centauri). Alpha Centauri A and B are Sun-like stars (Class G and K), and together they form the binary star Alpha Centauri AB. To the naked eye, the two main components appear to be a single star with an apparent magnitude of −0.27, the brightest star in the southern constellation of Centaurus and the third-brightest in the night sky, outshone only by Sirius and Canopus. Alpha Centauri A has 1.1 times the mass and 1.519 times the luminosity of the Sun, while Alpha Centauri B is smaller and cooler, at 0.907 times the Sun's mass and 0.445 times its luminosity. The pair orbit around a common centre with an
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Nomenclature

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α Centauri (Latinised to Alpha Centauri ) is the system's designation given by Johann Bayer in 1603. It bears the traditional name Rigil Kentaurus , which is a Latinisation of the Arabic name رِجْل القِنْطورُس ‎ Rijl al-Qinṭūrus, meaning 'the Foot of the Centaur'. The name is frequently abbreviated to Rigil Kent or even Rigil , though the latter name is better known for Beta Orionis (Rigel). An alternative name found in European sources, Toliman , is an approximation of the Arabic الظَّلِيمَان ‎ aẓ-Ẓalīmān (in older transcription, aṭ-Ṭhalīmān ), meaning 'the (two male) Ostriches', an appellation Zakariya al-Qazwini had applied to Lambda and Mu Sagittarii, also in the southern hemisphere. A third name that has been applied is Bungula ( / ˈ b ʌ ŋ ɡ juː l ə / ), of obscure origin. Allen can only surmise it may have been coined from the Greek letter beta (β) and Latin ungula 'hoof'. Alpha Centauri C was discovered in 1915 by Robert T. A. Innes, who suggest
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Stellar system

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Alpha Centauri is a triple star system, with its two main stars, Alpha Centauri A and Alpha Centauri B, being a binary component. The AB designation, or older A×B , denotes the mass centre of a main binary system relative to companion star(s) in a multiple star system. AB-C refers to the component of Proxima Centauri in relation to the central binary, being the distance between the centre of mass and the outlying companion. Because the distance between Proxima (C) and either of Alpha Centauri A or B is similar, the AB binary system is sometimes treated as a single gravitational object. Orbital properties edit The A and B components of Alpha Centauri have an orbital period of 79.91 years. Their orbit is moderately eccentric, e  = 0.5179; their closest approach or periastron is 11.2 AU (1.68 billion km), or about the distance between the Sun and Saturn; and their furthest separation or apastron is 35.6 AU (5.33 billion km), about the distance between the Sun and Pluto. The most recent
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Observation

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To the naked eye, Alpha Centauri AB appears to be a single star, the brightest in the southern constellation of Centaurus. Their apparent angular separation varies over about 80 years between 2 and 22 arcsec (the naked eye has a resolution of 60 arcsec), but through much of the orbit, both are easily resolved in binoculars or small telescopes. At −0.27 apparent magnitude (combined for A and B magnitudes), Alpha Centauri is fainter only than Sirius and Canopus. It is the outer star of The Pointers or The Southern Pointers , so called because the line through Beta Centauri (Hadar/Agena), some 4.5° west, points to the constellation Crux—the Southern Cross. The Pointers easily distinguish the true Southern Cross from the fainter asterism known as the False Cross. South of about 29° S latitude, Alpha Centauri is circumpolar and never sets below the horizon.note North of about 29° N latitude, Alpha Centauri never rises. Alpha Centauri lies close to the southern horizon when viewed from the
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Observational history

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Alpha Centauri is listed in the 2nd-century star catalog of Ptolemy. He gave its ecliptic coordinates, but texts differ as to whether the ecliptic latitude reads 44° 10′ South or 41° 10′ South . (Presently the ecliptic latitude is 43.5° South , but it has decreased by a fraction of a degree since Ptolemy's time due to proper motion.) In Ptolemy's time, Alpha Centauri was visible from Alexandria, Egypt, at 31° N, but, due to precession, its declination is now –60° 51′ South , and it can no longer be seen at that latitude. English explorer Robert Hues brought Alpha Centauri to the attention of European observers in his 1592 work Tractatus de Globis , along with Canopus and Achernar, noting: Now, therefore, there are but three Stars of the first magnitude that I could perceive in all those parts which are never seene here in England. The first of these is that bright Star in the sterne of Argo which they call Canobus. The second Achernar is in the end of Eridanus. The third Alph
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Kinematics

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All components of Alpha Centauri display significant proper motion against the background sky. Over centuries, this causes their apparent positions to slowly change. Proper motion was unknown to ancient astronomers. Most assumed that the stars are permanently fixed on the celestial sphere, as stated in the works of the philosopher Aristotle. In 1718, Edmond Halley found that some stars had significantly moved from their ancient astrometric positions. In the 1830s, Thomas Henderson discovered the true distance to Alpha Centauri by analysing his many astrometric mural circle observations. He then realised this system also likely had a high proper motion. In this case, the apparent stellar motion was found using Nicolas Louis de Lacaille's astrometric observations of 1751–1752, by the observed differences between the two measured positions in different epochs. Calculated proper motion of the centre of mass for Alpha Centauri AB is about 3620 mas (milli-arcseconds) per year toward the
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